At the lowest level, this effect is a partial and potentially inconsistent failure of a person's short-term memory. It can cause a general difficulty staying focused, an increase in distractibility, and a tendency to forget what one is thinking or saying.
Memory suppression is an inhibition of a person's ability to maintain a functional short and long-term memory.    This occurs in a manner that is directly proportional to the dosage consumed, and often begins with the degradation of one's short-term memory.
Memory suppression is a process that may be broken down into the 4 basic levels described below:
Partial short-term memory suppression
Complete short-term memory suppression
At this level, this effect is the complete failure of a person's short-term memory. This results in one being completely incapable of remembering any details regarding the present situation and the events leading up to it for more than a few seconds. This state of mind can often result in thought loops, confusion, disorientation, and a loss of control, especially for the inexperienced. At this level, it can also become impossible to follow both conversations and the plot of most forms of media.
Partial long-term memory suppression
At this level, this effect is the partial, often intermittent failure of a person's long-term memory in addition to the complete failure of their short-term memory. This results in one experiencing an increased difficulty recalling basic concepts and autobiographical information from their long-term memory. Compounded with the complete suppression of short-term memory, it creates an altered state where even basic tasks become challenging or impossible as one cannot mentally access past memories of how to complete them. For example, one may take a longer time to recall the identity of close friends or temporarily forget how to perform basic tasks. This state may create the sensation of experiencing something for the first time. At this stage, a reduction of certain learned personality traits, awareness of cultural norms, and linguistic recall may accompany the suppression of long-term memory.
Complete long-term memory suppression
At the highest level, this effect is the complete and persistent failure of both a person's long and short-term memory. This results in one becoming completely incapable of remembering even the most basic fundamental concepts stored within their long-term memory. This includes everything from their name, hometown, past memories, the awareness of being on drugs, what drugs even are, what human beings are, what life is, that time exists, what anything is, or that anything exists. Memory suppression of this level blocks all mental associations, attached meaning, acquired preferences, and value judgements one may have towards the external world. Sufficiently intense memory loss is also associated with the loss of a sense of self referred to as ego death, in which one is no longer aware of their own existence. In this state, the user is unable to recall all learned conceptual knowledge about themselves and the external world, and no longer experiences the sensation of being a separate observer in an external world.
It is worth noting that although memory suppression is vaguely similar in its effects to amnesia, it differs in that it directly suppresses one's usage of their long or short term memory without inhibiting the person's ability to recall what happened during the experience afterwards. In contrast, amnesia does not directly affect the usage of one's short or long-term memory during its experience; instead, it renders a person incapable of recalling events after it has worn off. A person experiencing memory suppression cannot access their existing memory, while a person with drug-induced amnesia cannot properly store new memories. As such, a person experiencing amnesia may not obviously appear to be doing so, as they can often carry on normal conversations and perform complex tasks. This is not the case with memory suppression.
Memory suppression is often accompanied by other coinciding effects such as thought loops, personal bias suppression, amnesia, and delusions. It is most commonly induced under the influence of moderate dosages of hallucinogenic compounds, such as psychedelics, dissociatives, and deliriants. 
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